Leica LTM BPM Prismeter

[Malcolm M]

Does anyone have any experience with the BPM Prismeter close-up attachment? They turn up fairly frequently and modest prices, and I have a strong desire to add one (or even two- there were different strengths) to my box of scarcely used Leica accessories.

Questions include-

How do the viewfinder lenses attach to the camera?

Does it work with all Barnack Leicas (especially the IIIg)?

I remember them advertising in the seventies, but it appears that the company was even smaller than I ever imagined- literally four blokes in a shed!

Macro Bellows - a complete guide to BPM Camera Bellows

Any advice gratefully received (except “Don’t waste your money.” I know that already).

 

[Dralowid]

Like this? This one will do up to IIIf but not IIIg I think. From memory the finder lenses are a push on fit.

Leica Leitz lens attachment B.P.M Prismeter No1 PLUS extras! | eBay UK

Leitz remote cable, marked with Leitz. Length of around 12" In original box.

www.ebay.co.uk

As an aside I saw a lot of bits that contained half a STEMAR but can't find it now...

 

[Coldkennels]

Unless they did one specifically for the IIIg that I've never seen, it'll be limited to the Leica II to the IIIf only. The layout/design of windows for the IIIg is too different - RF base is the same, but the bezels are smaller (nothing to clip onto), the frameline window would be blocked, and the VF is too large for the viewfinder window on the Prismeter. I think with the IIIg you're limited to the ADVOO for close focusing unless you want to use the BOOWU and get creative - it doesn't even fit into the Focoslide (although apparently a IIIg-compatible Focoslide does exist, but I've never seen one).

Personally, I'm not a fan of any of the close-focus widgets that use a diopter filter; I think they all degrade image quality slightly. Also, I own the Canon Auto-Up - basically an ADVOO for Canon's 50mm lenses - and it's bloody horrible to use, with some viewfinder blockage, alignment issues, and a huge amount of mass sticking out the very front of the camera. While the Prismeter is better than the ADVOO/Auto-Up design in every way, the NOOKY, NOOKY-HESUM and SOOKY are still much nicer arrangements (and amazingly accurate, including compensating for framing!) if you're looking for close focusing on a Barnack.

 

[Malcolm M]

Thanks for the responses. My thoughts were that the BPM might have more universal applicability than the Leica close-up devices, where pretty much every possible lens/camera combination seems to require another adapter.

If the goggles slip fit over the rangefinder windows, then as Coldkennels pointed out one of the said windows on the IIIg is undersized, and the one that isn't doesn't protrude as far as on the older models.

I already have a NOOKY, and my objections are twofold- one, the teensy amount of twist that supposedly secures the lens inspires no confidence that it won't fall off, and two, with two lugs for mounting the NOOKY, a focusing spar on the NOOKY, a (redundant) focusing spar on the lens and a screw on the lens hood, it's all too cluttered and I end up unscrewing the NOOKY instead of focusing the lens....



Plus, the eyepiece runs out of dioptre adjustment at these distances, but I don't suppose the Prismeter would help there.

 

[Dralowid]

I'm half looking for a NOOKY, not NOOKY HESUM but the Elmar one. Prices seem to be all over the place.

 

[Coldkennels]

I'm half looking for a NOOKY, not NOOKY HESUM but the Elmar one. Prices seem to be all over the place.

Check your DM's - I've just found a bunch at good prices!

I don't own the NOOKY, just the -HESUM and the SOOKY. I've handled a couple of NOOKY-HESUMs and there's a lot of variation; I've seen some my Summar drops straight out of, and some where it sits solidly. I suspect there must be a way to tighten them up, but I've never bothered trying to fettle mine, as it does the job without issue. I do sympathise with the "finding the right (focusing!) knob" issue, though. That still confuses me from time to time, too.

It is frustrating that you need to make sure you've got the right widget for the right lens, but I don't know just how widely compatible the Canon Auto-Up really is; I've seen some posts saying it'll work on anything with a front that is roughly 42mm in external diameter, regardless of focal length, but I've never tested it. Mine is marked specifically for the early 50/1.9 Serenar, but now I've got the Canon 50/1.8 fully cleaned up and focusing accurately, I should at least try it on that. Getting accurate framing is a nightmare, though. Here's the relevant section from the manual:




...yeah, I'll deal with the NOOKY's excessive amounts of knobby bits rather than deal with that, thanks.